Field of the Invention
The present invention relates to an organic thin film transistor, an organic semiconductor thin film, and an organic semiconductor material. More specifically, the invention relates to a compound having a dibenzocarbazole structure, an organic thin film transistor containing the compound, an organic semiconductor material for a non-light emitting organic semiconductor device containing the compound, a material for an organic thin film transistor containing the compound, a coating solution for a non-light emitting organic semiconductor device containing the compound, and an organic semiconductor thin film for a non-light emitting organic semiconductor device containing the compound.
Background Art
A device using an organic semiconductor material is expected to have various advantages as compared to an ordinary device using an inorganic semiconductor material, such as silicon, and thus is receiving much attention. Examples of the device using an organic semiconductor material include a photoelectric conversion device, such as an organic thin film solar cell and a solid state image sensing device, using an organic semiconductor material as a photoelectric conversion material, and a non-light emitting organic transistor. The device using an organic semiconductor material has a possibility that a device having a large area may be produced at a low temperature and a low cost, as compared to a device using an inorganic semiconductor material. Furthermore, the characteristics of the material may be easily changed by changing the molecular structure thereof, and thus there is a wide range of variations in materials, by which functions and devices that have not been achieved by an inorganic semiconductor material may be realized.
For example, Patent Document 1 describes a compound having two dibenzocarbazole structures in the molecule, and describes that the compound may be used in a light emitting layer and a hole transporting layer of an organic electroluminescence (which may be referred to as organic EL), and the compound is excellent in heat resistance and has high Tg. However, Patent Document 1 does not describe or suggest the purpose of an organic transistor.
Patent Document 2 describes a compound having a dibenzocarbazole structure, and describes that the compound is an organic EL material having high efficiency and high durability. However, Patent Document 2 does not describe or suggest the purpose of an organic transistor.
Patent Document 3 describes as a compound having a dibenzocarbazole structure a dibenzocarbazole compound having a structure containing benzene rings condensed at two positions that are the most remote from the N atom of carbazole, as an organic semiconductor compound, and describes that the compound has high solubility in an organic solvent. Patent Document 3 describes that the organic semiconductor compound may be applied to various purposes, and describes that the compound may be applied to a thin film transistor (TFT), but the examples thereof disclose only the production of a solar cell but do not disclose the production of an organic thin film transistor.
Patent Document 4 does not clearly describe a compound having a dibenzocarbazole structure, but describes that a compound having a benzocarbazole structure may be used as an organic EL material, and describes that a low driving voltage, a high current density, a high efficiency, a high quantum efficiency and a high luminance are achieved.